-----Original Message----- From: burlen <burlen@xxxxxxxxxxxxxxxxx> To: Dima Sorkin <dima.sorkin@xxxxxxxxx> Date: Wed, 12 Mar 2008 16:09:59 -0400 Subject: Re: fortran - changing precision of real numbers top-post elided Dima Sorkin wrote: > Hi. > I have a code written in single-precision (MIEV0.f by Wiscombe). > I want to compile and run it in double-precision. > > Is there some compiler options in gfortran ? > (in g77 ? (if I will have to use old computer)) > > In case the answer is 'no', is the following sufficient: > 1) change 'REAL' type to 'DOUBLE PRECISION' globally in the code. > 2) change all calls to 'REAL(..)' function by 'DBLE(..)'. > http://gcc.gnu.org/onlinedocs/ for gfortran: -fdefault-real-8 Set the default real type to an 8 byte wide type. g77 had no such option. It's difficult to imagine an old computer which could run g77 but not gfortran. Tim Prince
